Title

Author

Document Type

Thesis

Date of Degree

Spring 2015

Degree Name

MS (Master of Science)

Degree In

Oral Science

First Advisor

Justine L. Kolker

Abstract

Objectives: This retrospective cohort study aimed to assess the survival time and factors associated with survival of anterior composite-resin restoration placed at the University of Iowa, College of Dentistry (UICOD).

Methods: Patients at the UICOD who had anterior composite restorations placed between 1995-1997 and could be followed through 2013 were included in this study. Factors included: patient age and gender, tooth type (central or lateral incisor, or canine) and location (maxillary or mandibular), restoration size (1, 2, 3, 4 and more surfaces), provider type (dental student, graduate student, faculty), and clinic (operative, family, or other clinics) where the initial restoration placed. Survival time of a restoration was defined as how long a restoration lasted from the day of placement until the day of subsequent treatment. Subsequent treatment included: restorations, veneer and/or crowns, root canal therapy, and extraction. One restoration per patient was used for the study. Statistical analyses consisted of the Kaplan-Meier analysis and Cox regression (alpha=0.05).

Results: Of the 668 subjects (mean±SD age=55±13 years and 60.8% females) who fulfilled the inclusion criteria, the mean±SD survival time of composite resin restoration was 11±7 years and an overall survival rate was 43.3%. Patients' gender, age, tooth location, and clinic type were not significantly associated with the survival time of composite resin restoration. Cox regression model indicated that significant differences in the restoration hazards were found on tooth type (p=0.002), provider type (p=0.003) and restoration sizes (p=0.0072). Central (HR=1.59; CI=1.23-2.07) and lateral (HR=1.36; CI=1.03-1.79) incisors had a significantly higher hazard ratio (HR) than canines, and faculty had significantly lower HR than undergraduate students (HR=0.68, CI=0.55-0.85). Restorations sizes one surface (HR=0.6; CI=0.44-0.81) and two surfaces (HR=0.65; CI=0.48-0.88) had significantly lower HR than four and more surfaces restorations.

Conclusion: The mean and median survival time of anterior composite restoration at UICOD was 11 and 13 years, respectively. Tooth type, provider type, and restoration size were significant predictors for the survival time of anterior composite-resin restoration.

Public Abstract

Objectives: This study aimed to assess the longevity and factors associated with longevity of tooth colored fillings in front teeth placed at the University of Iowa, College of Dentistry (UICOD).

Methods: Patients who received a filling in a front tooth between 1995-1997 and who could be followed through 2013 were included in this study. Factors included: patient age and gender, tooth type (central or lateral incisor, or canine), tooth location (upper or lower), restoration size, provider type (dental student, graduate student, faculty), and clinic where the restoration was placed. Filling longevity was defined as how long a filling lasted from the day of placement until the day of additional treatment.

Results: The data of 668 patients were included in this study; the average longevity of anterior fillings was 11 years. Patients’ gender, age, tooth location, and clinic type were not noticeably associated with the longevity of a filling in the front teeth. Statistical tests found tooth type, provider type, and restoration size had an effect on the longevity of fillings in the front teeth. Fillings placed in central and lateral incisor teeth did not last as long as fillings placed in canine teeth. Fillings placed by faculty lasted longer than fillings placed by graduate and dental students. Smaller fillings lasted longer than larger fillings.

Conclusion: Fillings placed in front teeth at UICOD lasted for an average of 11 years. Tooth type, provider type, and restoration size had noticeable effect on the longevity of fillings in front teeth.